Pt基及Pd基催化剂的制备及其对葡萄糖电催化氧化性能研究

发布时间：2018-03-20 03:18

本文选题：Pt基催化剂　切入点：Pd基催化剂　出处：《烟台大学》2017年硕士论文　论文类型：学位论文

【摘要】：葡萄糖是自然界中最丰富的单糖,有较高的理论能量值,被完全氧化可释放约2870k J/mol的能量,从中获得有用的化学能转化为电能是一种很好的选择,故被广泛的应用于工业生产。贵金属Pt、Pd是最为常见的直接燃料电池的阳极催化剂材料,然而Pt、Pd基催化剂存在易中毒、利用率低、成本高等缺点。本论文通过向贵金属Pt、Pd中添加过渡金属制备二元合金催化剂,然后对载体进行改性的方法,来提高催化剂的催化性能、增强其抗CO中毒性能,并降低其使用成本。我们系统的研究了所制备的催化剂在葡萄糖直接燃料电池(DGCE)中的应用。通过XRD、TEM、XPS以及多种电化学测试手段对所制备的催化剂的结构及活性稳定性进行了表征和测试。其具体研究内容概括如下:1.通过乙二醇浸渍还原方法向Pt催化剂中添加第二种金属Sn制备一系列Pt-Sn/C催化剂。通过控制Pt量、溶液p H和Pt/Sn原子比等条件制备不同的催化剂探究它们对葡萄糖电催化氧化能力的大小。结果表明,在Pt的负载量为5%、溶液p H=9以及Pt/Sn原子比为3时催化剂的催化性能最好。2.在以上条件下,添加Ni、Co两种过渡金属,同样采用乙二醇浸渍还原法制备Pt-M/C催化剂,对比不同金属对催化剂催化性能的影响,对比发现Pt3Sn1/CPt3Ni1/CPt3Co1/CPt/C;本小节实验在此基础上又采用壳聚糖(CHI)对载体进行改性制备CHI不同负载量的Pt3Sn1/C-CHI。结果表明:壳聚糖修饰量为1%时,催化剂催化性能较好;继续向Pt/C-CHI催化剂中添加第二金属Ni、Co,得出Pt3Sn1/C-CHIPt3Co1/C-CHIPt3Ni1/C-CHIPt3Sn1/CPt/C-CHIPt/C。3.通过硼氢化钠还原法制备Pd-Co/C二元金属催化剂,通过改变Pd负载量、溶液p H及Pd/Co原子比,寻找催化剂催化葡萄糖氧化的规律。结果表明催化剂在Pd负载量为5%,溶液p H=9,Pd/Co原子比为3时表现出较好的催化性能;同时XRD、TEM、XPS及ESCA等结果表明:第二金属Co的加入减小了Pd2+浓度,增加了Pd0百分含量,提高了Pd的分散度与电化学活性表面积,从而提高了Pd的利用率及其催化性能。
[Abstract]:Glucose is the most abundant monosaccharide in nature. It has a high theoretical energy value. Completely oxidized can release about 2870 k J / mol of energy, and it is a good choice to obtain useful chemical energy and convert it into electric energy. Therefore, it is widely used in industrial production. Precious metal PTO PD is the most common anode catalyst material for direct fuel cell. In this paper, binary alloy catalyst was prepared by adding transition metal to precious metal PtPd, and then modified the support to improve the catalytic performance of the catalyst and enhance its resistance to CO poisoning. We systematically studied the application of the prepared catalyst in glucose direct fuel cell (DGCE). The structure and activity of the prepared catalyst were stable by XRDX TEMX XPS and various electrochemical methods. The properties were characterized and tested. The specific research contents were summarized as follows: 1. A series of Pt-Sn/C catalysts were prepared by adding a second metal Sn to Pt catalyst by dipping reduction method of ethylene glycol. Preparation of different Catalysts for glucose Electrocatalytic Oxidation of glucose under different conditions such as pH and Pt/Sn Atomic ratio. The results show that, Under the conditions of Pt loading of 5, solution pH 9 and Pt/Sn atom ratio 3:00, the catalyst has the best catalytic performance. Under the above conditions, the Pt-M/C catalyst was prepared by glycol impregnation reduction with the addition of two transition metals. Comparing the effects of different metals on the catalytic performance of the catalyst, it was found that Pt3Sn1 / CPt3Ni1 / CPt3Co1 / CPt3Co1 / CPT / C; on the basis of this experiment, chitosan was used to modify the support to prepare Pt3Sn1 / C-CHI with different amounts of CHI. The results showed that when the amount of chitosan modified was 1%, The catalytic performance of the catalyst was better, and the second metal NiancoCo was added to the Pt/C-CHI catalyst, and it was obtained that Pt3Sn1 / C-CHIPt3Co1 / C-CHIPt3Ni1 / C-CHIPt3Sn1 / C-CHIPt1 / C.3.The binary Pd-Co/C catalyst was prepared by sodium borohydride reduction method, and the catalyst was prepared by changing the PD loading, solution pH and Pd/Co atomic ratio. The results showed that the catalyst exhibited good catalytic performance at PD loading of 5 and the atomic ratio of PD / Co in solution was 3:00. The results of XRD-Tem XPS and ESCA showed that the concentration of Pd2 decreased with the addition of the second metal Co. The percentage content of Pd0 was increased, the dispersion of PD and the surface area of electrochemical activity were increased, thus the utilization ratio of PD and its catalytic performance were improved.
【学位授予单位】：烟台大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：O643.36;TM911.4

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